The present invention relates to a circuit for indicating the battery voltage in still or motion-picture cameras. Typically, such monitoring and indicating circuits include a controllable-conductivity semiconductor element connected to the battery, and in the circuit of such element, an indicator element; the semiconductor element is conductive when the battery voltage is within the range of its operative (usable) values, and the indicator element indicates that this is the situation.
With typical prior-art battery-monitoring circuitry, the indicator element is illuminated until such time as the battery voltage has dropped to the lower limit of its usable values. When the battery voltage is near this lower limit, the indication provided by the indicator element is typically more or less indefinite, unreliable or unstable.